Improved accessibility, editing and ease of use in Google Sites
Several accessibility improvements have been made to Google Sites, ranging from new keyboard shortcuts for editors (like Alt+Shift+F for opening the editor toolbar) to better viewing experiences for readers. Editors can now also set image width to 100% of the screen width and easily customize the font, color, and size of lower-level headers (H2, H3, and H4 tags).*
Release Track:
Rapid release, with Scheduled release coming later in June [*customization of lower-level headers was previously launched to Rapid only and is now launching to Scheduled]
For more information:
Reference by : http://www.google.com/